Based on the following information from ABC Corporation, calculate ABC's contribution margin per unit.

Selling price per unit	$100
Direct materials per unit	$20
Direct labor per unit	$15
Variable manufacturing overhead per unit	$10
Fixed manufacturing overhead per unit	$18
Sales commissions per unit	$9
Fixed selling costs per unit	$12

A: $37 per unit.

B: $55 per unit.

C: $16 per unit.

D: $46 per unit.